In numerous commercial applications, it is desirable to mass produce a variety of identifiably shaped three-dimensional objects. For example, in the food industry it is frequently desirable to produce food items such as crackers, cookies, snacks, pet foods, pasta and confections that are in the form of animals, letters, vehicles, etc.
Designing and producing edible items in a specific shape is often an inherent part of a marketing strategy of a company, and product shape often plays a crucial role in consumer identification of a food product. In the pet food industry, in particular, it is common practice to produce products in which the food items are produced in a highly recognizable abstract shape or a shape representing a typical food for a pet such as bone-shaped "treats" for dogs or fish-shaped "treats" for cats.
A variety of methods exist in the art to produce three-dimensional objects from material that is capable of being extruded or formed and then solidified. For example, many products such as toys and game pieces are formed via injection molding.
Three-dimensional food items are commonly formed via some sort of extrusion technique. For example, complex shaped pasta products such as shells, rotini, and the like are typically formed by extruding the pasta gluten through an orifice or die using differential pressure so that one portion of the pasta material is extruded faster than an adjoining portion. This differential pressure causes three-dimensional twisting and curling of the resulting pasta product. This sort of extrusion technique, however, does not allow fine control of the shape of the resultant product and thus does not allow the creation of identifiable tangible three-dimensional objects such as those in the likeness of animal shapes or letters.
Van Lengerich et al. have described in International Patent No. WO 93/10662 a method of producing farinaceous-based food products in the shape of animals. Dough is extruded through a multi-port extrusion die and cut by two distinct sizes of knives mounted on a continuous or oscillating cutter. Two knives pass over each extrusion port in sequence as the dough is being extruded. The first and shorter of each pair of knives passes across only a portion of each of the die ports, partially cutting each of the extrudate ropes of dough. The second and longer knife of each pair completely cuts each of the partially cut extrudate ropes into individual identifiable pieces. Utilizing this method, one can produce three-dimensional confectioneries which have, for example, individual identifiable subparts such as legs or wheels. Such objects however are little more than base-reliefed two-dimensional forms and are not free standing. In addition, such an extrusion and cutting assembly is not readily capable of being modified to produce alternative shaped objects.
Therefore, there is a need for an apparatus and method capable of producing objects of "true" three-dimensional design which is readily re-toolable to produce a variety of designs.